Cranes



Oct. 18, 1966 F. FLOER 3,279,329

CRANES Filed Sept. 28, 1964 5 SheetsSheet 1 F/NN FLOER.

INVENTOR:

F. FLOER Oct. 18, 1966 CRANES 3 Sheets-Sheet 2 Filed Sept. 28, 1964 INVENTOR: F/NN FLUER.

F. FLOER Oct. 18, 1966 CRANES 5 Sheets-Sheet 5 Filed Sept. 28, 1964 INVENTORZ F/NN FLOER.

United States Patent CRANES Finn Floer, Moss, Norway, assignor to A/ S Bergens Mekaniske Verksteder, Bergen, Norway Filed Sept. 28, 1964, Ser. No. 399,695 Claims priority, application Norway, Oct. 3, 1963, 150,322 4 Claims. (Cl. 92-67) This invention relates to cranes and more particularly to ships cranes.

It has previously been proposed to pivot the boom or extension arm of ships cranes about a vertical or substantially vertical axis by means of a hydraulic pivotal arrangement. Hitherto, applicants have constructed ships cranes in which the boom bolt or horizontal journal of the boom, has been secured at the top of the axle in a hydraulic rotary motor of known type in which the axle carries radially directed vanes received in working chambers. In this way, pivoting of the boom bolt is effected in the same manner as in the known hydraulic rudder-controlled machines. Moreover, it is also known to bring about such pivoting of the crane arms and the like, by means of Worm gear transmissions which when hydraulic operation is desired, are driven by a hydraulic motor, generally a hydraulic rotary motor.

By utilizing hydraulic rotary motors of the kind known per se in which the axle carries radially directed vanes received in pressure chambers, it has hitherto only been possible to achieve a very limited pivotal angle. In these rotary motors, the pivotal axle must, in fact, be balanced for side pressure so that at least two vanes or wings must be employed on the axle. However, the pivotal angle is limited to about 140 by virtue of the stationary partitions present in these known rotary motors.

It is an object of the present invention to provide a particularly simple construction of rotary mechanism for pivoting a jib crane in which large pivotal angles along with high turning moments can be achieved.

According to the present invention a crane arrangement comprises a combination of a hydraulic rotary motor and a crane arm operatively connected thereto for pivotal movement about an approximately vertical axis of rotation of said motor, the latter comprising motor portions each capable of pivoting over a limited pivotal angle, said portions being coupled together to enable the motor to turn through an angle equal to a multiple of the pivotal angles of said motor portions and to impart this movement to said crane arm.

Preferably, the motor portions each comp-rise two groups of chambers each of which groups is arranged in communication with a corresponding one of the groups of an adjacent motor portion and each group associated with a given motor portion, being adapted to be fed hydraulic fluid under pressure while the remaining group is connected to discharge, the force exerted by the hydraulic fluid within the chambers having the effect of pivoting said motor portions in a given direction.

In order that the invention can be more fully understood, an embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which:

FIGURE 1 is a schematic elevation view of a portion of the crane arrangement in accordance with the present invention,

FIGURE 2 is a vertical section of the hydraulic rotary motor included in the crane arrangement of FIGURE 1,

FIGURE 3 is a plan view including part of the crane arrangement shown in FIGURE 1,

FIGURE 4 is a plan view of a base ring used in the crane arrangement of FIGURE 1,

3,279,329 Patented Oct. 18, 1966 ice FIGURE 5 is a horizontal section taken on the line VV of FIGURE 2,

FIGURE 6 is a horizontal section taken on the line VIVI of FIGURE 2,

FIGURE 7 is a horizontal section taken on the line VII--VII of FIGURE 2, and

FIGURE 8 is a horizontal section taken on the line VIIIVIII of FIGURE 2.

In FIG. 1 a ships mast 10 is seen in which the latter is joined to a boom or extension arm 11 by a boom bolt 12, which is received in bearings 13. The bearing lugs 14 for these hearings are, as will be seen from FIG. 3, fixed on a supporting plate 15, which is fixed to the upper shaft journal 16 in a hydraulic rotary motor arrangement, designated generally by 17. The construction and mode of operation of the latter will be explained further in the following description.

The shaft journal 16 is also received in a horizontal bearing 18, which is fixed to a bracket 19, which is secured to the mast 10. To the bearing 18 there is also secured a holder 21 for a pulley 22 for the hoisting line 23 of the loading winch (not shown).

On the deck construction 24 by the mast 10 there is arranged a base ring 25. In the latter there is fixed a lower shaft journal 26 in the hydraulic rotary motor arrangement 17. It will be seen from FIG. 1 that two hydraulic conduits 27, 28 pass from the lower side of the deck construction 24 and into the hydraulic rotary motor arrangement 17. These conduits come, as will be seen from the schematic representation, from a hydraulic control valve 29, which is connected via two conduits 30, 31 to a hydraulic pump 32. By means of the control valve 29, which is a conventional four-way valve of wellknown construction, pressure oil can be fed as desired to one or the other of the conduits 27, 28, while the other conduit, 28 or 27 respectively, is connected to the discharge back to the pump.

The hydraulic rotary motor arrangement is illustrated in detail in FIG. 2. The afore-mentioned lower shaft journal 26 is fixedly connected to a first, lower boss 33, a shaft 34 and a second, upper boss 35. To the shaft 34 there are fixed two diametrically opposed vanes or wings 36, 37, which extend radially outwards and terminate in alignment with the bosses 33 and 35. These parts 26, 33, 34, 35, 36 and 37 together constitute a rigid unit, which in reality is a rotor in a rotary motor, the housing of which is formed by a uniformly thick pipe 38 which is disposed around these parts and receives them in the lower half of its bore 39. To the inner wall of this bore there are secured two diametrically opposed blocks 40, 41, which extend inwards towards the shaft 34 and bear tightly against the latter and against the inner sides of the bosses 33 and 35.

It will be evident from FIGS. 5 and 6, which illustrate cross-sections through the parts, that there is formed in this way pressure chambers 42A and 42B between the vane 36 and the block 40 and the vane 37 and the block 41 respectively, and pressure chambers 43A and 43B between the vane 36 and the block 41 and the vane 37 and the block 40 respectively. The first set of pressure chambers 42A and 42B are connected to each other via a radially extending bore 44 (FIG. 5) and to the conduit 27 via an axially extending bore 45 through the boss 33. The second pressure chambers 43A and 43B are connected to each other via a radially extending bore 46 (FIG. 6), and to the conduit 28 through an axially extending bore 47 through the boss 33.

As indicated above, the parts 26, 33, 34, 35, 36 and 37 are received in the lower half of the pipe 38. In the upper half there is received a rotor with a lower boss 48, a shaft 49, and an upper boss 50. To the upper boss 50 is fixed the upper journal shaft rotary motor arrangement 17.

To the shaft 49, there are secured two diametrically opposed vanes or Wings 51, 52 which extend radially outwards and terminate in alignment with the bosses 48, 50. In the same manner as before these parts, 16, 48, 49, 50, 51 and 52 constitute a rotor in a rotary motor, the housing of which is formed by the pipe 38. In this case also there are secured to the inner wall of the bore 39, two diametrically opposed blocks 53, 54, which extend inwards towards the shaft 34 and bear tightly against the later and against the bosses 48 and 50.

From FIGS. 7 and 8, which illustrate cross-sections through the upper part of the pipe 38, it will be evident, that pressure chambers 55A and 55B are formed between the vane 52 and the block 54 and between the vane 51 and the block 53 respectively, and pressure chambers 56A and 56B between the vane 51 and the block 54 and between the vane 52 and the block 53 respectively. The pressure chambers 55A and 55B are connected to each other via a bore 57 (FIG. 7) through the shaft 49, and the pressure chambers 56A and 56B are connected to each other via a bore 58 (FIG. 8). Furthermore pressure pipes 59, 60 are arranged on the outer side of the pipe 38, of which the former connects the first set of pressure chambers 42A and 42B in FIG. with the first set of pressure chambers 55A and 55B in FIG. 7 (see FIG. 2) and the latter connects the second set of pressure chambers 43A and 43B in FIG. 5 with the second set of pressure chambers 56A and 56B in FIG. 7 (see FIG. 2).

In FIG. 2, gaskets 61 are shown which seal off the individual parts in the rotary motor.

It will now be apparent, with reference to FIG. 5, that when pressure oil is fed to the conduit 27 and from there to the pressure chambers 42A and 42B, while the conduit 28 and with it the pressure chambers 43A and 43B are connected to the return conduit back to the pump, a pressure is produced which operates against the vanes 36, 37 in the clockwise direction, and against the blocks 40, 41 in the counterclockwise direction. Since the vanes 36, 37 are fixedly connected to the shaft 34, and with it to the shaft journal 26, which in turn is fixed to the deck construction 24 via the base ring 25, these parts will be kept stationary while the blocks 40, 41 are urged in the counter-clockwise direction. The pipe 38 which these blocks are fixedly connected to, will therefore turn in this direction.

The upper rotor will thus twist or turn relative to the lower, fixed rotor. However, pressure oil is fed, as mentioned above, to the pressure chambers 55A and 553 through the pressure pipe 59 from the pressure chambers 42A, 42B, and a pressure is therefore exerted against the vanes 51, 52 in the counter-clockwise direction. Since this rotor can turn freely, apart from its connection to the boom, these vanes 51, 52 will be urged in the counterclockwise direction.

It is assumed now 16 in the hydraulic that the various pressure chambers in the rotary motor arrangement are of equal size. On this assumption, as the shaft journal 16 is pivoted, the pivotal angle will be equal to double that of the pivot shaft as the pipe 38 is pivoted relative to the shaft journal 26. Since it is possible to pivot the pipe 38 through an angle of about 140 relative to the shaft journal 26, the shaft journal 16 can thus be pivoted about 280 relative to the shaft journal 26. Pivoting of the boom can thus be achieved to the same maximum amplitude, as is indicated in dotted lines in FIG. 3.

In the construction which is usually employed for ships cranes, namely with a mast or post which receives a top rope by which a boom is suspended, this pivotal amplitude of 280 represents substantially the maximum effective pivotal angle, as the mast will lock on further pivoting. However, it is also possible, if this should be desirable, to obtain a larger pivotal angle, thus over 360", namely about 420, by utilizing three rotors positioned one after the other in a common pipe-shaped housing. Likewise it is also possible to obtain a higher turning moment in the hydraulic motor by employing three vane rotors. Certainly in this case the maximum pivotal angle will be less, namely about 170480", but this can in turn be compensated for by using for example as mentioned three rotors arranged axially one after the other in a common pipe.

The embodiment described for a boom-pivoting arrangement is very simple and robust and gives a high turning moment. Two important features of the arrangement are firstly that the radial forces on the pivotal shaft are substantially uniform, since diametrically opposed pressure chambers are employed, and secondly that it is easy to obtain excellent sealing of the pressure oil-containing chambers against the atmosphere and against the pressure-free chambers. This makes it possible to use relatively high pressures in the system, whereby the turning moment can be further increased without having to increase the dimensions of the pivotal arrangement.

What I claim is:

1. In a crane the combination of a hydraulic rotary motor and a crane arm operatively connected thereto for pivotal movement about an approximately vertical axis of rotation of the motor, said motor including a pivotable pipe member on the inner wall of which are fixed first and second sets of diametrically opposed dividing walls arranged in spaced apart relation longitudinally thereof, a first motor portion fixedly mounted Within said pipe member and including outwardly directed radial vanes adapted to form with said first set of dividing walls two groups of chambers, a second motor portion pivotably mounted within said pipe member and also including ont- -wardly directed radial vanes adapted to form with said second set of dividing walls two additional groups of chambers, means communicating each group of chambers of said first motor portion with a corresponding one of the groups of the second motor portion, and means for supplying hydraulic fluid under pressure to corresponding groups of chambers of said first and second motor portions while the other corresponding groups are connected to discharge, the force exerted by the hydraulic fluid on said first set of dividing walls and on the radial vanes of said second motor portion having the effect of concurrently pivoting the pipe member and said second motor portion in the same direction, whereby the motor is turned through an angle equal to the sum of the angular movement of the pipe member and the angular movement of the second motor portion relative to the pipe member and this said sum of the angular movements is imparted to said crane arm by said second motor portion.

2. A crane according to claim 1, wherein the means for supplying hydraulic fluid under pressure comprises a pair of conduit means, a hydraulic control valve and a hydraulic pump, said conduit means passing from said pump via said control valve to the first motor portion and each communicating with a corresponding one of the groups of chambers of said first motor portion.

3. In a crane the combination of a hydraulic rotary motor and a crane arm operatively connected thereto for pivotal movement about an axis of rotation of said motor, said motor comprising a fixed portion, a first portion rotatably mounted with respect to said fixed portion, a second portion rotatably mounted with respect to said first portion, means associated with said port-ions to define two respective groups of chambers between the fixed and the first portion and between the first and second portions, means establishing communication between corresponding chambers ofsaid two respective groups of chambers, and means for supplying pressure fluid to said corresponding chambers to develop a force within the chambers and produce rotation of said first portion and concurrent relative rotation of the second portion with respect to the thus rotated first portion whereby said second portion undergoes absolute rotation with respect to the fixed portion equal to the sum of the relative rotations of the first and second portions, said second portion being adapted for connection with the crane arm to impart angular movement thereto.

4. In a crane the combination of a hydraulic rotary motor and a crane arm operatively connected thereto for pivotal movement about an axis of rotation of said motor, said motor comprising a plurality of portions arranged successively along its axis, each portion defining two groups of chambers, means communicating each of said groups of chambers with the corresponding groups of the other portions, said portions each including two relatively movable members one of which is common with the next successive portion and means for supplying pressure fluid to either of the groups of chambers while the other group is connected to discharge to develop a force References Cited by the Examiner UNITED STATES PATENTS 691,692 1/1902 Zweigbergk 91167 2,911,956 11/1959 Smith 92-67 2,988,057 6/1961 Litz 91167 MARTIN P. SCHWADRON, Primary Examiner.

SAMUEL LEVINE, Examiner.

I. C. COHEN, Assistant Examiner. 

3. IN A CRANE THE COMBINATION OF A HYDRAULIC ROTARY MOTOR AND A CRANE ARM OPERATIVELY CONNECTED THERETO FOR PIVOTAL MOVEMENT ABOUT AN AXIS OF ROTATION OF SAID MOTOR, SAID MOTOR COMPRISING A FIXED PORTION, A FIRST PORTION ROTATABLY MOUNTED WITH RESPECT TO SAID FIXED PORTION, A SECOND PORTION ROTATABLY MOUNTED WITH RESPECT TO SAID FIRST PORTION, MEANS ASSOCIATED WITH SAID PORTIONS TO DEFINE TWO RESPECTIVE GROUPS OF CHAMBERS BETWEEN THE FIXED AND THE FIRST PORTION AND BETWEEN THE FIRST AND SECOND PORTIONS, MEANS ESTABLISHING COMMUNICATION BETWEEN CORRESPONDING CHAMBERS OF SAID TWO RESPECTIVE GROUPS OF CHAMBERS, AND MEANS FOR SUPPLYING PRESSURE FLUID TO SAID CORRESPONDING CHAMBERS TO DEVELOP A FORCE WITHIN THE CHAMBERS AND PRODUCE ROTATION OF SAID FIRST PORTION AND CONCURRENT RELATIVE ROTATION FIRST PORTION WHEREBY SAID SECOND PORTION THE THUS ROTATED FIRST PORTION WHEREBY SAID SECOND PORTION UNDERGOES ABSOLUTE ROTATION WITH RESPECT TO THE FIXED PORTION EQUAL TO THE SUM OF THE RELATIVE ROTATIONS OF THE FIRST AND SECOND PORTIONS, SAID SECOND PORTION BEING ADAPTED FOR CONNECTION WITH THE CRANE ARM TO IMPART ANGULAR MOVEMENT THERETO. 